Chilling message on bathroom wall

A CALIFORNIA school was placed in lockdown after a chilling threat was scrawled on a bathroom wall in permanent marker.

San Leandro High School was on high alert after a threat appeared on the wall reading: "I'm shooting the school tommorow (sic) at 1. I'm sick of this s**t. Better not come. F**k this place."

The disturbing warning was found on the boys' bathroom wall.

Police issued a community message just before 11.10am.

San Leandro Unified School District Superintendent Mike McLaughlin said the graffiti was found in the boys' bathroom on Wednesday morning, according to KTVU.

"We brought in police department staff and we systematically searched the school," he said. "We also brought in some K-9's (police dogs) to search the hallways, and do a very comprehensive search the best we can to ensure the safety of the school, students and staff.

"However this message was written with the intended violence to take place tomorrow.

"We didn't want to take the chance and have this take place tomorrow. We decided to work with the school and clear the grounds today - just as a precaution."

The lockdown has since been lifted, and authorities have denied rumours of guns found on campus.

News of the threat came as thousands of students across the Bay Area were participating in a national "March For Our Lives" walkout calling for tighter gun control laws in the wake of the Florida shooting.